1. Field of the Description
The present invention relates, in general, to projecting or displaying video/animated or still three dimensional (3D) images, and, more particularly, to autostereoscopy and autostereoscopic projection systems such as those adapted to display ghost or latent 3D images as provided as part of a Pepper's ghost illusion.
2. Relevant Background
There are numerous entertainment and other settings where it is desirable to create a unique visual display. For example, theme or amusement parks may include rides or walk-through attractions where guests (or “viewers”) are entertained by a unique visual effect or illusion.
Pepper's ghost is an illusionary technique used by magicians, by ride or attraction designers, and others to produce a 3D illusion of a latent or ghost-like image. Using a simple piece of plate glass and special lighting techniques, Pepper's ghost systems can make objects appear and disappear within a scene or room. Generally, these systems include a main room or scene that is readily viewed by a guest or viewer and also include a hidden room that is not visible to the viewer. Both rooms may be identical in their physical structure including furniture and other objects except that the hidden room may include additional objects or characters such as a ghost. A large piece of glass or a half-silvered mirror is situated between the viewer and the scene at an angle such as about 45 degrees. When the main room is lit and the hidden room is darkened, the viewer only sees the main room as the hidden room does not reflect from the glass, which is itself hard to see as it typically extends across the entire view of the main room and is transparent (at least in part) to allow viewing of the room behind the glass (or reflective element).
Pepper's ghost becomes visible to the viewer when the entire hidden room or portions such as the ghost or other character are brightly lit. Since only a portion of the light cast upon the ghost or other objects in the hidden room is reflected from the glass, the reflected images appear as latent or ghostly images relative to the objects in the main room (e.g., the reflected images or images superimposed in the visible room may appear to float). The Pepper's ghost image is a 3D image that may be still or animation may be provided such as with animatronics or by placing a live actor in the hidden room. In some other implementations, the hidden room may be replaced by a projection assembly that projects a still or animated image onto a screen, such as a rear projection screen, and images on this projection screen (which is hidden from view from the viewer) are reflected from the glass or reflective element (or reflective surface of the reflective element which may be a half-silvered mirror or a flexible material with similar optical qualities to provide a reflective surface).
In amusement park and other settings, it is often desirable to permanently (or nearly so) install Pepper's ghost-based displays as part of attractions such as part of a haunted house. In such extended use implementations, sustainability and maintainability of the reflective element and its surfaces is very important for long term performance without degradation in the quality of the displayed or created Pepper's ghost (or reflected imagery). Hence, there remains a need for improved designs for systems or assemblies for providing the Pepper's ghost illusion that provide high quality imagery over long time periods that are easy to maintain and install.